Barrel positioning means for automatic pistol



Jan. 8, 1957 F. E. sTuRTl-:VANT 2,776,602

ARREL POSITICNING MEANS FOR AUTOMATIC PISTOL Filed Sept. 25, 1955 Figi,za sz Z3 45 57 44 l 6 4 2 4 zo 59)?,2 @W5 l/,2 N i968 66 so, Q s+44e. 4o

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6c -IN1/Emule. FOSTER E. StumzvANr United States Patent O BARRELPOSITIONING MEANS FOR AUTOMATIC PISTOL Foster E. Sturtevant, WestHartford, Conn., assignor, by

mesne assignments, to Colts Patent Fire Arms Manufacturing Company,Incorporated, Hartford, Conn., a corporation of Delaware ApplicationSeptember 25, 1953, Serial No. 382,295

9 Claims. (Cl. 89--196) The invention relates to an automatic pistol ofthe type comprising a frame having a grip portion, comprising a barrelconnected with the frame, comprising a slide guided on the upper portionof the frame for recoil movement relatively to the said frame andrelatively to the barrel, comprising a reaction spring for opposingrecoil movement of the slide and for returning it to its forwardposition after recoil, and Comprising firing mechanism on the frame andslide.

The principal object of the invention is to provide a pistol of the typespecified having improved means for the accurate positioning of thebarrel with respect to the slide during functioning of the pistol. Inattaining this object the reaction spring is utilized for maintainingthe axis of the barrel at the front end thereof in xed relationship withthe slide.

A further object of the invention is to provide certain parts which maybe substituted in a previously or separate- 1y constructed pistol inorder to attain the said principal object of the invention.

Other objects of the invention will be apparent from the drawing andfrom the following description.

In the drawing I have shown in detail a preferred embodiment of theinvention, but it will be understood that various changes may be madefrom the construction shown, and that the drawing is not to be construedas defining or limiting the scope of the invention, the claims forming apart of this specification being relied upon for that purpose.

Of the drawing:

Fig. 1 is a combined side and longitudinal sectional view of anautomatic pistol embodying the invention.

Fig. 2 is a fragmentary view similar to the sectional portion of Fig. 1,but showing some of the parts in different relative positions.

Fig. 3 is a transverse sectional view taken along the line 3 3 of Fig.l.

Fig. 4 is a transverse sectional view taken along the line 4 4 of Fig.l.

Fig. 5 is a fragmentary front end view.

Fig. 6 is a view similar to Fig. 5 but showing the connection member inadifferent position.

Fig. 7 is an enlarged fragmentary partly schematic view similar to theright portion of Fig. 2 and showing the action of the connecting member.

As to many of its features, an automatic pistol embodying the inventionmay be of known construction. While the invention is not so limited, theloading and ring mechanism may be generally similar to those disclosedin the Tansley Patent No. 1,719,384 dated July 2, 1929.

In general the pistol comprises a frame 10 having a grip portion 12 anda forwardly extending upper portion 14. A slide 16 is guided on theupper part of the frame for rectilinear rearward and forward movement,tongue and groove formations 17, 17 being provided for this purpose. Ashereinafter more fully explained, a main reaction spring 18 biases theslide 16 toward its forward 2,776,602 Patented Jan. 8, i957 position asshown in Fig. 1. A barrel 20 engages the slide 16 and is partly enclosedthereby, the barrel having the usual bore and having a cartridge chamber21. The rear portion 22 of the slide 16 constitutes the breechblock,this breechblock portion 22 being behind the barrel and having a frontface 23 engageable with the rear of the barrel when the slide 16 is inforward position. The breechblock also has a face 24 which is positionedto engage the rear face of the head of a cartridge in the chamber 21 ofthe barrel when the slide is in forward position.

Suitable front and rear sights 26 and 28 are provided on the slide 16.One of the sights is preferably vertically adjustable by anyconventional or suitable means. The rear sight 28 is shown as being soadjustable.

The breechblock portion 22 of the slide carries a longitudinally movablefiring pin 30 which is biased to its relatively rearward position by aspring 32. A pivoted spring-pressed hammer 34 is carried by the framefor engaging the firing pin 30 to eiect tiring, the hammer as shown inFig. 1 being in its cocked position. The hammer 34 can be released bypressing a trigger 36, the hammer then moving so as to strike the tiringpin 30 and thus effect firing. The mechanism for the release of thehammer by means of the trigger may be similar to the mechanism for thispurpose shown in the said Tansley patent. Upon tiring, the slide 16moves rearwardly as the result of recoil and in opposition to thereaction spring 18 and in so moving it engages the hammer 34 to restorethe hammer to its cocked position. Following recoil movement, thereaction spring 18 returns the slide to its forward position.

During the recoil movement of the slide the empty cartridge shell isextracted from the chamber in the barrel and is ejected through theejection opening 37. The extracting and ejecting means are or may beconventional and are not shown.

The grip portion 12 of the frame is hollow and is adapted to receive acartridge magazine 38, the upper portion of which is shown in Fig. 2.The magazine 38 serves in the conventional manner to successively supplycartridges to a position in which each cartridge is engaged by the face24 of the breechblock 22 and is forced into the chamber 21 of the barrelwhen the slide and the breechblock are moved forwardly after recoil.

The pistol is preferably provided with a pivoted grip safety member 40which is movable forwardly from the position shown in Fig. 1 by the handof the user when the grip portion 12 of the frame and the trigger 36 areengaged to effect tiring. Firing can be effected only when the gripmember 40 has been moved to its forward position.

The rear portion of the barrel engages the frame and the slide in such amanner that it is held with its axis in fixed relationship with the saidframe and slide at the instant of tiring. The manner of engagement ofthe rear portion of the barrel with the frame and with the slide may bevaried, but as shown an enlarged rearward portion 42 of the barrelclosely and accurately tits a semicylindrical recess 44 in the slide 16,the said recess being open at the bottom. A horizontal downwardly facingsurface 45 on the barrel near the rear thereof engages an upwardlyfacing surface on the frame, the two surfaces cooperating to hold theenlarged portion 42 of the barrel in engagement with the slide recess44. Thus the rear portion of the barrel is held with its axis in xedrelation to the slide, relative longitudinal rectilinear movement beingnevertheless permitted. With the described construction the barrel isdirectly held by the slide and the frame, no links or other relativelymovable parts being provided.

As shown, the barrel 20 has a lug 46 which extends downwardly throughthe open bottom of the slide recess 44, the said lug being at the frontof the surface 45. The lug 46 has a transversely extending slot 48 and apin 50 extends through the said slot and through holes in the sides ofthe frame 16, the pin being in a normally fixed position. The pin S isremovable to permit disassembly of the pistol. The barrel is movablerearwardly and forwardly to a limited extent relatively to the frame andit is biased for forward movement by a spring 52 which is in a hole inthe lug 46 and which abuts at its rear end against a vertical face 54 onthe frame 10. Rearward movement of the barrel is limited by theengagement of the lug 46 with the frame face 54 as shown in Fig. 2.Forward movement of the barrel is limited by the engagement of the rearof the slot 48 with the pin 50 as shown in Fig. 1.

The rear portion of the reaction spring 18 is within a longitudinalrecess 55 in the front portion 14 of the frame, the said recess beingopen at the top thereof. A guide pin 56 is positioned within the spring,this pin having a head 58 which abuts against a shoulder in the framerecess 55 so that rearward movement is prevented. The head 58 serves asan abutment for the rear end of the spring 18. The enlarged portion 42of the barrel prevents upward movement of the said head 58 and of therear end of the guide pin 56.

A forwardly biased pressure or abutment member 60 is provided which islongitudinally movable to a limited extent with respect to the slide.Preferably the front portion of the reaction spring 1S engages the saidmember 60 and serves as the means for biasing it. The abutment member ispreferably a tube closed at the front, the front end of the spring beingwithin the tube. When the pressure or abutment member is a tube asshown, it ts and is longitudinally movable within a longitudinal hole ina depending portion 62 of the slide 16. The front end portion of thepressure or abutment member has an upwardly facing cam surface which isinclined upwardly and rearwardly. When the pressure or abutment memberis a tube, the said cam surface is a part of an annular conical surface64 at the front of the tube.

A control member 66 is provided in association with the front portionsof the slide and barrel and with the abutment member or tube 60. Thesaid control member includes a sleeve 68 which surrounds the frontportion of the barrel 20 and which is within a paitly cylindrical recess69 in the front portion of the slide 16, the cylindrical portion of thesaid recess extending for more than l80 and the said aperture having anopening 70 at the bottom thereof as shown in Fig. 4. The control member66 also includes a radially projecting lug 71 which is on the sleeve 68and is entered in an arcuate groove 72 in one side of the slide recess69. By reason of its entry in the groove 72 as shown in Fig. 4, the lug71 prevents relative longitudinal movement between the control memberand the slide. The control member 66 is provided with a downwardlyfacing cam surface which is positioned and shaped for engaging the saidcam surface on the abutment member or tube 60. As shown, the saidcontrol member is provided near the front of the sleeve 68 with a flange74 which projects radially in the downward direction. The said iiangehas an arcuate partly conical cam surface 76 which engages and iits theconical cam surface 64 on the tube 60. By reason of the interengaged camsurfaces the control member 66 serves to connect the abutment member ortube 60 with the slide 16 so that the reaction spring 18 acts at alltimes to bias the slide forwardly. Forward movement of the slide islimited by the engagement of the breechblock face 23 with the barrel asshown in Fig. l, forward movement of the barrel being prevented by thepin 50.

In order to release the tube 60 the said tube is first moved rearwardlyin opposition to the spring 18, and then the control member 66 is turnedin the clockwise direction from the position shown in Fig, to theposition shown in Fig. 6. When the control member 66 is moved to theFig. 6 position, the lug 71 remains in the groove 72 and the controlmember is still connected with the slide 16. With the control member 66turned as shown, the tube 60 and the spring 18 may be removed forwardly.After the tube 60 has been removed, the control member 66 may be turnedin the counterclockwise direction to and beyond the Fig. 5 position soas to bring the lug 71 out of the groove 72 and into register with theslide opening 70. The control member may then be removed from the slidein the forward direction.

When the trigger 36 is pressed to release the hammer 34, the firing pin30 engages the primer of the cartridge in the chamber 21 to effectfiring. When firing occurs the slide 16 and the barrel 20 initially moverearwardly in unison as the result of recoil, the slide moving inopposition to the reaction spring 18 and the barrel moving in oppositionto the spring 52. This movement in unison continues until movement ofthe barrel is stopped by the engagement of the barrel lug 46 with theface 54 on the frame. Thus the barrel and the bolt portion 22 of theslide are maintained in engagement for a brief instant after firing.Fig. 2 shows the parts in an intermediate position following firing, thebarrel having been moved fully rearwardly and the slide having beenmoved rearwardly only to the same extent as the barrel. The design issuch that the bullet leaves the barrel while the barrel and the slideremain in engagement.

By reason of the inertia of the slide the rearward movement thereofcontinues after barrel movement has been stopped. During the continuedrearward movement of the slide the cartridge shell is extracted andejected and the hammer is restored to its cocked position as previouslydescribed. The subsequent forward movement of the slide by the reactionspring moves a cartridge from the magazine into the barrel chamber 21 asalso previously described.

The rear and front portions of the barrel must be accurately held infixed positions with respect to the slide except as to relativelongitudinal movement, particularly at the instant of firing. The rearportion of the barrel is so held by the engagement thereof with thepartly cylindrical slide recess 44 and with the frame. The front portionof the barrel would be so held if there were exact accuracy of titbetween the barrel and the interior of the sleeve 68 and between theexterior of the said sleeve and the slide recess 69. However, such exactaccuracy of tit at the front is not always practicable, and in practiceit may be desirable to intentionally provide small clearances betweenthe barrel and the sleeve 66 and between the said sleeve and the sliderecess 69. With a pistol embodying the invention the front portion ofthe barrel is accurately held notwithstanding such clearances.

The action of the control member and of the parts associated therewithwill be more clearly understood by reference to Fig. 7 which is anenlarged partly schematic view similar to the front portion of Fig. 2.It has been assumed that the front portion of the barrel does notclosely fit the interior of the sleeve 63 and that the exterior of thesaid sleeve does not closely tit the recess 69 in the slide. Theclearances have been exaggerated for purposes of illustration.

The inclined cam surface 64 on the forwardly biased tube or abutmentmember 60 and the mating inclined cam surface 76 on the control member66 constitute interengaging means not only for causing the controlmember to limit forward movement of the abutment member with respect tothe slide but also for causing the said abutment member to bias the saidcontrol member upwardly at least at the front end thereof, By reason ofthe assumed clearances the control member 66 is slightly tilted in thecounterclockwise direction about a transverse axis as shown in Fig. 7,the lug 71 serving as a pivot for the tilting movement. The sleeve 68 isforced into engagement with the slide at the point 78 and is forced intoengagement with the barrel at the points 80 and 82. It will be apparentthat, for the illustrated tilting action, the clearance between thesleeve and the slide recess must be at least as great as that betweenthe barrel and the sleeve. With the control member 66 tilted as shown,the front portion of the barrel is accurately held in fixed positionwith respect to the slide except as to relative longitudinal movement.The rear portion of the barrel is held as before described and it istherefore apparent that the entire barrel is always accuratelypositioned with respect to the slide at the instant of firing,notwithstanding any looseness of tit at the front between the barrel andthe sleeve and between the sleeve and the slide recess.

There may be small variations from the intended clearances withcorresponding variations in the position of the front portion of thebarrel. Any such variations can be compensated for by adjusting the rearsight 28 so that the line of sight is in proper relationship to the axisof the barrel when the barrel is held as shown in Fig. 7.

From the foregoing description and from the drawing it will be apparentthat the control member 66 comprises a sleeve 68 surrounding the frontportion of the barrel 20, comprises a radially projecting lug 71 on thesleeve 68 at one side thereof for entry into an arcuate groove 72 in theslide 16, and also comprises a radially extending ange 74 on the sleeve68 at one end thereof and spaced in one direction from the lug 71, thesaid flange 74 being formed with a cam surface which conforms to theconical cam surface 64 on the tube 60. By reason of the describedrelationship of the parts, it will be evident that the cam surface 76conforms to the surface of a cone having its axis parallel to the axisof the sleeve 68 and having its apex spaced from the plane at the saidend of the sleeve in the same direction in which the ange 74 is spacedfrom the lug 71.

The abutment member or tube 60 and the control member 66 are adapted foruse as substitute parts in a previously or separately constructed pistolgenerally similar to that shown and described but not initiallyincorporating the present invention.

The invention claimed is:

l. The combination in an automatic pistol, of a frame, a longitudinalbreech slide guided for longitudinal movement along the frame, alongitudinal barrel, means for holding the rear portion of the barrelwith its axis in rigid, fixed relation to the axis of the slide whilepermitting relative longitudinal rectilinear movements, a longitudinalreaction spring for opposing rearward recoil movement of the slide andfor then returning the slide to its forward position, a forwardly biasedpressure member located near the front of the slide and longitudinallymovable to a limited extent with respect thereto, a control memberconnected for longitudinal movement in unison with the slide and forlimited transverse movement relative thereto, the said control membercomprising a sleeve slidably mounted upon t'ne front portion of thebarrel and located within a recess in the front portion of the slide,and interengaging means on the forwardly biased pressure member and onthe control member for causing the said pressure member to bias the saidcontrol member for transverse movement relative to the slide and barrel,so as to hold the front portion of the barrel in fixed axial relationwith the slide while permitting relative longitudinal rectilinearmovements of said slide and barrel.

2. An automatic pistol as set forth in claim 1, wherein theinterengaging means comprise interengaging cam surfaces locatedrespectively on the pressure member and on the control member, wherebythe forwardly biased action of said pressure member causes a limitedtransverse movement of said control member with respect to said pressuremember and said barrel.

3. The combination in `an automatic pistol, of a frame, a longitudinalbreech slide guided for longitudinal movement along the frame, alongitudinal barrel, means for holding the rear portion of the barrelwith its axis in rigid, fixed relation to the axis of the slide whilepermitting relative longitudinal rectilinear movements, a longitudinalreaction spring held at its rear in iixed relation to the frame, anabutment member near the front of the slide and longitudinally movableto a limited extent with respect thereto which member is forwardlybiased by the reaction spring, a control member connected forlongitudinal movement in unison with the slide and for limitedtransverse movement relative thereto, the said control member comprisinga sleeve slidably mounted upon the front portion of the barrel andlocated within .a recess in the front portion of the slide, andinterengaging means on the forwardly biased abutment member and on thecontrol member for enabling the reaction spring to oppose rearwardrecoil movement of the slide and to then return the slide to its forwardposition and for also causing the said abutment member to bias the saidcontrol member for transverse movement relatively to the slide andbarrel, so as to hold the front portion of the barrel in fixed axialrelation with the slide while permitting relative longitudinalrectilinear movements of said slide and barrel.

4. The combination in an automatic pistol, of a frame, a longitudinalbreech slide guided for longitudinal movement along the frame, alongitudinal barrel, means for holding the rear portion of the barrelwith its axis in rigid, fixed relation to the axis of the slide whilepermitting relative longitudinal rectilinear movements, a. longitudinalreaction spring for opposing rearward recoil movement of the slide andfor then returning the slide to its forward position, a forwardly biasedpressure member located near the front of the slide and longitudinallymovable to a limited extent with respect thereto, a control memberconnected for longitudinal movement in unison with the slide andcomprising a sleeve slidably mounted upon the front portion of thebarrel and located within a recess in the front portion of the slide,small clearances being provided between the front portion of the barreland the sleeve and between the sleeve and the slide recess, andinterengaging means on the forwardly biased pressure member and on thecontrol member for causing the said pressure member to bias the saidcontrol member for tilting movement relative to the slide about atransverse axis so as to hold the front portion of the barrel in fixedrelation with the slide while permitting relative longitudinalrectilinear movements.

5. The combination in an automatic pistol, of a frame, a longitudinalbreech slide guided for longitudinal movement along the frame, alongitudinal barrel, means for holding the rear portion of the barrelwith its axis in rigid, fixed relation to the axis of the slide whilepermitting relative longitudinal rectilinear movements, a longitudinalreaction spring held at its rear in fixed relation to the frame, anabutment member near the front of the slide and longitudinally movableto a limited extent with respect thereto which member is forwardlybiased by the reaction spring, a control member connected forlongitudinal movement in unison with the slide and comprising a sleeveslidably mounted upon the front portion of the barrel and located withina recess in the front portion of the slide, small clearances beingprovided between the front portion of the barrel and the sleeve andbetween the sleeve and the slide recess, and interengaging means on theforwardly biased abutment member and on the control member for enablingthe reaction spring to oppose rearward recoil movement of the slide andto then return the slide to its forward position and for also causingthe said abutment member to bias the said control member for tiltingmovement relative to the slide about a transverse axis so as to hold thefront portion of the barrel in fixed relation with the slide whilepermitting relative longitudinal rectilinear movements.

6. The combination in an automatic pistol, of a frame, a longitudinalslide guided for longitudinal movement along the frame, a longitudinalbarrel, means for holding the rear portion of the barrel with its axisin rigid, fixed relation to the axis of the Slide while permittingrelative longitudinal rectilinear movements, a longitudinal reactionspring having its rear end held in fixed relation to the frame, anabutment member near the front of the slide and longitudinally movableto a limited extent with respect thereto, the said member being inengagement with the front end of the reaction spring so as to be biasedfor forward movement/and having an upwardly facing cam surface which isinclined upwardly and rearwardly, and a control member connected forlongitudinal movement with the slide and also for limited transversemovement relative thereto which control member comprises a sleeveslidably mounted upon the front portion of the barrel and located withina recess in the front portion of the slide, the said control member alsocomprising a downwardly facing cam surface engaging the cam surface onthe abutment member and similarly inclined, which cam surfaces on theabutment member and on the control member limit forward movement of theabutment member with respect to the slide so as to enable the reactionspring to forwardly bias the said slide and which cam surfaces also biasthe said control member for limited transverse movement relative to theslide so that the sleeve of the said member holds the front portion ofthe barrel with its axis in fixed axial relation to the slide whilepermitting relative longitudinal rectilinear movements.

7. The combination in an automatic pistol, of a frame having a gripportion, a longitudinal slide guided for longitudinal movement along theframe, a longitudinal barrel, means for holding the rear portion of thebarrel with its axis in rigid, fixed relation to the axis of the slidewhile permitting relative longitudinal rectilinear movements, alongitudinal reaction spring having its rear end held in fixed relationto the frame, an abutment tube near the front of the slide and below thebarrel and longitudinally movable toa limited extent with respect to thesaid slide, the said tube being closed at its front and being inengagement with the front end of the reaction spring so as to be biasedfor forward movement and the said tube having a convex conical camsurface at the front, and a control member connected for longitudinalmovement with the slide and also for limited transverse movementrelative thereto, which control member comprises a sleeve slidablymounted upon the front portion of the barrel and located within a recessin the front portion of the slide, the said control member alsocomprising a downwardly extending flange on the sleeve having adownwardly facing conically shaped cam surface engaging and fitting theconical cam surface on the abutment tube, which cam surfaces on theabutment member and on the flange of the connection member limit forwardmovement of the abutment tube with respect to the slide, so as to enablethe reaction spring to forwardly bias the said slide, and which camsurfaces also bias the control member for transverse movement relativeto the slide so that the sleeve of the said member holds the frontportion of the barrel with its axis in fixed relation to the slide whilepermitting relative longitudinal rectilinear movements.

8. A subassembly for use in an automatic pistol comprising, a barrel, abreech slide, an abutment tube closed at one end and having a convexconical cam surface at the said end which tube is adapted for receivingthe end portion of a reaction spring, and a control member comprising asleeve slidably mounted on said barrel, said sleeve havingan aperturefor receiving the front portion of said barrel and comprising a radiallyprojecting lug on the sleeve at one side thereof for entry into anarcuate groove in a recess in saidslide and also comprising a radiallyextending flange on the sleeve at one end thereof and spaced in onedirection from the said lug, the said flange being formed with a camsurface which is shaped to fit the conical cam surface on the tube whenthe connection member is so positioned that the sleeve axis is parallelwith the tube axis; said cam surfaces coacting so that a longitudinalmovement of said tube causes a transverse movement of said controlmember with respect to said barrel and tube, whereby said control memberholds the front portion of said barrel in fixed axial relation to saidslide.

9. For use in an automatic pistol having a barrel and a breech slide, aconnection member comprising a sleeve having an aperture for receivingthe front portion of said barrel and comprising avradially projectinglug on the sleeve at one side thereof for entry into an arcuate groovein a recess in said slide; said member also comprising a radiallyextending flange on the sleeve at one end thereof and spaced in onedirection form the said lug, the said flange being formed with a camsurface which conforms to the surface of a cone-shaped cam on said slidehaving its axis parallel to the axis of the sleeve and having its apexspaced in the said direction from the plane of the said end of thesleeve; said cam surfaces coacting so that a longitudinal movement ofsaid slide causes a transverse movement of said connecting member withrespect to said barrel and slide, whereby said control member holds thefront portion of said barrel in fixed axial relation to said slide.

References Cited in the file of this patent UNITED STATES PATENTS2,489,816 Reilly Nov. 29, 1949 2,627,686 Shockey Feb. l0, 1953 FOREIGNPATENTS 673,028 Great Britain May 28, 1952

